Re: [PATCH net] net/sched: cls_fw: allow filter replace without re-specifying mask

[Wei Tao]

Hi Jakub,

> You are expected to reply to these questions. If this is an LLM-based
> report please be more considerate of maintainer's time. If you actually
> use this feature please include the response to the question above in
> the commit message and repost. The repost should not carry a Fixes
> tag, it's not a real bug.

This was found during an LLM-assisted review of the classifier
->change() replace paths, then verified manually and reproduced in a
QEMU VM.  The hint came from the cls_route in-place replace fixes
(41e85e54e564 and b72e025ac556); auditing other classifiers showed that
cls_fw has the opposite problem: fnew->id is inherited correctly, but
fw_set_parms() treats a replace like a create and rejects it when
TCA_FW_MASK is omitted.

I will drop the Fixes tag and post the v2 once net-next reopens.

Thanks,
Wei Tao